Battery service life indicator

Abstract

The electronic apparatus is provided with a device for informing the operator of information on the service life of the battery employed for driving the electronic apparatus.

What we claim is: 
     
       1. An electronic apparatus comprising: detecting means for detecting a variable output voltage level of a battery;   storage means for previously storing datum corresponding to a predetermined output voltage level of said battery;   life time memory means for storing life time datum of said battery, said life time datum being associated with the datum stored in said storage means;   comparison means for comparing the voltage level detected by said detecting means with the datum stored in said storage means; and   means for reading out the life time datum stored in said life time memory when said comparison means produces a coincidence of the output voltage level of said battery with the datum stored in said storage means.   
     
     
       2. An electronic apparatus according to claim 1 further comprising: numerical display means for displaying the life time datum read out from said reading means.   
     
     
       3. An electronic apparatus comprising: detecting means for detecting a variable output voltage level of a battery;   storage means having a plurality of memory locations for previously storing different data each corresponding to a respective predetermined output voltage level of said battery, and being stored in the associated one of the memory locations, respectively;   life time memory means having a plurality of memory locations for previously storing different life time data each being associated with the datum stored in each of the memory locations of said storage means, respectively;   comparison means for comparing the voltage level detected by said detecting means with the data stored in said storage means; and   means for reading out the associated life time datum stored in said life time memory means when said comparison means produce a coincidence of the output voltage level of said battery with the datum stored in any of the memory locations of said storage means.   
     
     
       4. An electronic apparatus according to claim 3 further comprising: numerical display means for displaying the life time data read out from said reading out means.   
     
     
       5. An electronic apparatus comprising: switch means for selecting one of a plurality of batteries having different life times;   means for identifying the battery selected by said switch means;   detecting means for detecting a variable output voltage level of the selected battery;   storage means having a plurality of memory locations for previously storing different data each corresponding to a respective predetermined output voltage level of said battery, and being stored in the associated one of the memory locations, respectively;   a plurality of groups of life time memory means each having a plurality of memory locations for previously storing a set of life time data each being associated with the datum stored in each of the memory locations of said storage means, respectively, wherein the respective sets of life time data in the groups are different from each other in correspondence to said batteries having the different life times;   group selecting means for selecting associated ones of said plurality of groups of life time memory means in accordance with the signal from said battery identifying means;   comparison means for comparing the voltage level detected by said detecting means with the data stored in said storage means; and   means for reading out the associated life time datum stored in the life time memory means of the one group selected by said group selecting means when said comparison means produces a coincidence of the output voltage level of said battery with the datum stored in any of the memory locations of said storage means.   
     
     
       6. An electronic apparatus according to claim 1 wherein said storage means comprise a Read Only Memory. 
     
     
       7. An electronic apparatus according to claim 1 wherein said comparison means comprise exclusive OR logic circuit means. 
     
     
       8. An electronic apparatus according to claim 1 wherein said life time memory means comprise a Read Only Memory. 
     
     
       9. An electronic apparatus according to claim 3 wherein said comparison means comprise an exclusive OR logic circuit means. 
     
     
       10. An electronic apparatus according to claim 3 wherein said life time memory means comprise a Read Only Memory. 
     
     
       11. An electronic apparatus according to claim 5 wherein said comparison means comprise an exclusive OR logic circuit means. 
     
     
       12. An electronic apparatus according to claim 5 wherein said life time memory means comprise a Read Only Memory. 
     
     
       13. An electronic apparatus comprising: storage means for storing data representative of a life time of a battery;   time counting means for counting time;   detecting means for detecting a coincidence of the output of said time counting means and the life time data stored in said storage means;   means responsive to the coincidence output from said detecting means for informing an operator of the termination of the life time of said battery; and   reset means responsive to a leading edge of the output level of said battery incorporated with said electronic apparatus for clearing said time counting means.   
     
     
       14. An electronic apparatus according to claim 13 further comprising control means for causing said time counting means to change the time counting basis in accordance with the status of operation of said battery. 
     
     
       15. An electronic apparatus comprising: detecting means for detecting an output level of a battery incorporated with said apparatus;   electronic read only memory means having a plurality of memory address locations for previously storing different data each being representative of the remainder of the life time of the battery associated with a respective predetermined output level of the battery, and each different datum being stored in an associated one of said memory address locations, respectively;   means connected to said memory means and said detecting means for comparing the output level of the battery detected by said detecting means with the predetermined output levels of the battery associated with said different data representative of the remainder of the life time of the battery, and for reading out the datum representative of the remainder of the life time of the battery, from the memory address location in which it is stored, associated with the predetermined output level of the battery detected by said detecting means; and   display means for selectively displaying the remainder of the life time of the battery read out by said comparing and reading out means.   
     
     
       16. An electronic apparatus according to claim 15 wherein said display means includes a numerical display means for displaying the remainder of the life time of the battery.